Final Report Summary - MELISSA (MEasurement of Lichen and Seed Survival through non-invasive Assessment of metabolic activity) • Summary description of the project objectives: The overall aim of MELISSA was to develop non-invasive techniques to diagnose cell viability of desiccation tolerant plant tissues (seeds and lichens) and to match these non-invasively obtained fingerprints with changes in the metabolite profile assessed through metabolomics. MELISSA also aimed at contributing to the disentangling of the metabolic and biophysical mechanisms that underpin tolerance to desiccation in plant tissues. Additionally, according to the objectives of the Intra-European fellowships for career development (IEF Call 2012), a strong emphasis was put on supporting the career development of the researcher (Beatriz Fernández-Marín), to enhance her scientific skills and competence and overall, to support her development towards a mature scientist capable of attaining a leading independent position, supported and mentored by the Scientist in charge, Prof. Ilse Kranner, University of Innsbruck, Austria.• Description of the work performed since the beginning of the project:Work on MELISSA was divided into five workpackages (WP), whereby WP1 and WP2 were dedicated to seeds, and WP3 and WP4 were dedicated to lichens. WP5 was dedicated to dissemination, knowledge transfer, training and outreach. In Year 1, most progress was made on the scientific research on lichens, and on dissemination and training (with a focus on infrared thermal imaging and lichen-handling procedures), and outreach activities (also focusing on lichens). In Year 2, most progress was made on the scientific research on seeds, and on dissemination, training (with a focus on volatile organic compounds (VOC) and metabolomics and on seed-handling procedures) and outreach (focused on seeds and plant desiccation tolerance).• Description of the main results achieved so far: The main results achieved by MELISSA can be summarised in five major points: 1) A purpose-built chamber was developed that allows control of the internal environmental conditions at high relative humidity for the recording of thermal fingerprints during hydration of lichens and seed material, without damage to the infrared camera and without artefacts due to water condensation. 2) New techniques for artificial ageing were developed for lichens, based on state-of-the-art techniques used for seeds. 3) A method was developed that allows non-invasive diagnosis of viability in lichen and seed material through the assessment of thermal fingerprints during water uptake, without the interference of evaporative cooling. 4) A method was developed that allows non-invasive monitoring of VOC emitted by seeds or lichens during ageing. 5) The molecular mobility in dry lichens was studied, providing the first evidence for lichens about the absence of enzymatic reactions in the glassy state (a highly viscous state reached upon severe dehydration).• Expected final results and their potential impact and use (including the socio-economic impact and the wider societal implications of the project so far): Main progress is expected in two areas, firstly, changes in metabolites (assessed through metabolomics) and VOC can be associated with the thermal fingerprints (monitored non-invasively) during ageing and hydration of seeds and lichens. Secondly, an integrated view of the metabolism of stressed desiccation-tolerant organisms, seeds and lichens, and an integrated view of the metabolic reactions that characterise viable plant material upon the early rehydration phase can be achieved. The new knowledge gained through MELISSA will be of relevance to the seed industry and to seed banks, to the benefit of agriculture and conservation. Germination testing to assess viability can be time-consuming and destroys germplasm. Non-invasive techniques for monitoring seed viability (as those developed by MELISSA) could save valuable seed collections, and may also serve as an early warning system for impending viability loss to allow intervention, for example regeneration of seed collections, to take place.